| (19) |
 |
|
(11) |
EP 0 878 607 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
19.05.1999 Bulletin 1999/20 |
| (43) |
Date of publication A2: |
|
18.11.1998 Bulletin 1998/47 |
| (22) |
Date of filing: 13.05.1998 |
|
| (51) |
International Patent Classification (IPC)6: E21B 43/22 |
|
| (84) |
Designated Contracting States: |
|
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE |
|
Designated Extension States: |
|
AL LT LV MK RO SI |
| (30) |
Priority: |
13.05.1997 US 855049
|
| (71) |
Applicant: Halliburton Energy Services, Inc. |
|
Duncan,
Oklahoma 73536 (US) |
|
| (72) |
Inventor: |
|
- Brezinski, Michael M.
2597 AN The Hague (NL)
|
| (74) |
Representative: Wain, Christopher Paul et al |
|
A.A. THORNTON & CO.
Northumberland House
303-306 High Holborn
London WC1V 7LE
London WC1V 7LE (GB) |
|
| |
|
| (54) |
Quaternary ammonium compounds useful for inhibiting metal corrosion |
(57) Quaternary ammonium compounds useful as metal corrosion inhibitors in aqueous acid
solutions, are made by contacting the still bottoms residue produced in the distillation
of quinoline from coal tar, with oxygen to oligomerize the aromatic amines contained
therein, and then reacting the oligomerized amines with a benzylhalide.